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W oodworkers want a router bit to do just two things: cut cleanly and stay sharp a long time. But with a long list of companies selling bits, it’s hard to identify the top-of-the-line performers. So to find out how bits measure up when it comes to smoothness and longevity, we purchased the same-style bit from 18 companies and tested the lot. The bit goes by several names. Commonly called a cove-and- bead bit, it also can be labeled a bead-and-cove bit, a roundingover cove bit, or a classical bit. We chose that bit because it cuts two profiles, a cove and a bead, with a shallow step in between. As a result, we could evaluate the bit’s ability to make a concave cut, a convex cut, and two sharp corners. Our goal was to use carbide-tipped bits with a 1⁄4-in. radius on both the cove and the bead. However, we soon learned that some are available only with a radius of 3⁄16 in., or a combination of 3⁄16 in. and 1⁄4 in. So, with one exception, all the bits we tested have cove and bead radii that range from 1⁄4 in. to 3⁄16 in. The Holbren bit is the exception, as it creates a 1⁄4-in. cove and a 3⁄8-in. bead. However, we did not see a significant correlation between size of bit and test results. Also, we tested only bits with 1⁄2-in.-dia. shanks. How we tested the bits The tests were done on a rock-solid router table with a massive fence made specifically for the test. A sturdy 31⁄4-hp fixed-base router provided the get-up-and-go. A power-feeder ensured that the test stock was fed through each bit at a constant rate of 5 ft. per minute (fpm), a speed that mimicked our typical hand-feed rate. Each bit was tested with the fence in line with the bearing, so the bit would make a full cut. The test was designed to include a number of materials, feed rates, and grain orientations, as well as performance after a few hundred feet of wear. First, we made edge-grain cuts on 30-in. lengths of knot-free sugar maple, black cherry, red oak, and eastern white pine, four woods that offer a mix of hardness and cutting characteristics. We also made end-grain cuts on 6-in.-wide sections of the same woods. Finally, we made edgegrain cuts on 30-in. lengths of Premium MDF (medium-density fiberboard) a product that, unlike regular MDF, has the same density across the entire thickness, allowing us to better evaluate the cut quality of each bit. Then, to accelerate wear on each bit, we cut through 100 ft. of standard MDF, which, according to a number of experts and manufacturers, would equal at least 200 ft. of hardwood. After that, we repeated the edge-grain, end-grain, and Premium MDF tests. Not surprisingly, all the bits lost sharpness after cutting the 100 ft. of MDF. When the tests were completed, our cuts on all the bits totaled nearly a half mile. Before the test started, to level the play- ing field, we planed all the boards to 3⁄4-in. thickness. Also, because wood can vary from one board to another, we made sure each type of test cut was always made on the same board. At the end of the test, we had 216 carefully labeled sample strips. Then, in a blind test, four editors independently Photos, except where noted: Michael Pekovich; this page (top two): Tom Begnal BITS WERE TESTED ON A VARIETY OF WOODS Longevity, too. Each bit made test cuts on edge grain (facing page), end grain (above), and then Premium MDF (right). Then, to accelerate wear, the testers ran 100 ft. of standard MDF past each bit. After that, they ran the edge grain, end grain, and Premium MDF cuts again. Two bits stood out At the end of the day, the Whiteside (left) and the Eagle (right) bits had risen to the top of the mix, tying for the highest score. Lee Valley had the second-highest score, followed by Southeast and Woodtek in a tie for third. By the way, White- side also had the best bit when we reviewed straight bits in our August 1999 issue (FWW #137). We named the Eagle and Whiteside bits best overall. And, since the Whiteside had one of the lowest prices of the top bits, we also named it best value. M AY / J U N E 2 0 0 7 47 S S S A A A U U U T T T O H O H O H O O O I I I R R HR H H C C C ’ ’ ’ C C C E E E